This invention relates generally to radar systems for monitoring moving targets by emission of radiant energy pulses and reception of target reflected echo pulses to provide data with respect to range and velocity of the target.
Pulse radar system heretofore involved generation of a continuous RF carrier wave by a transmitter that is intermittently operated so as to radiate RF pulses toward the target from which reflected echo pulses received by an antenna are fed to a superhetrodyne radio receiver. The received pulses were demodulated and typically processed to provide signal measurement data from which target range and velocity are calculated.
In an effort to improve operational reliability of pulse echo receiving systems under a wide range of adverse environmental conditions, various interrelated transmitter and pulse timing control arrangements have been proposed as disclosed for example in U.S. Pat. Nos. 3,794,996 to Robbins et al. U.S. Pat. No. 3,983,422 to Nicolson et al., on the other hand, proposes a control arrangement for an interrelated transmitter and pulse echo receiving system to eliminate circuit adjustments. Such prior pulse radar systems have never-the-less had various operational noise problems due to target scintillations and multipath errors as well as limited range accuracy. They have also been susceptible to electronic jamming and stealth techniques.
It is therefore an important object of the present invention to provide a pulse radar system with interrelated transmitter and receiver pulse timing controls which overcomes the aforementioned noise problems, including those externally induced by deliberate jamming and use of stealth techniques.